A blade server is a stripped-down server computer with a modular design optimized to minimize the use of physical space and energy. Blade servers have many components removed to save space, minimize power consumption, and account for other considerations. A blade enclosure, which can hold multiple blade servers, provides services such as power, cooling, networking, various interconnects and management. Together, blades and the blade enclosure form a blade system.
In some situations, these blade systems could be installed in both the front end and rear end of an equipment rack. In these situations, cooling air typically enters the front of the rack, possibly from a cold aisle, and exits through the rear of the rack, possibly into a hot aisle. The blade system may manage the various airflow paths through the rack to insure the cooling air is drawn from (and exhausted to) the appropriate volumes. One example of a blade system is the Advanced Telecommunications Computing Architecture (AdvancedTCA or ATCA) standard for modular electronic packaging from the PCI Industrial Computer Manufacturer's Group (PCIMG).